Temporal trends in the surgical outcomes of patients with breast cancer

BACKGROUND: The incidence of breast cancer has been increasing in Japan over the past three decades, and it is the currently the most common malignancy in Japan. This study investigated the temporal trends of the surgical outcomes in patients with breast cancer. METHODS: We evaluated 543 consecutive patients who underwent breast-cancer resection between 1980 and 2009. The temporal trends in the surgical outcome and clinicopathological features were evaluated separately for the periods covering 1980 to 1989, 1990 to 1999, and 2000 to 2009. RESULTS: The number of patients who underwent resection during these three respective periods were 133, 176, and 234, respectively. All patients were women. The percentage of patients at stages 0 or 1 was 63.2%, 58.5%, and 43.6%, respectively, during the three periods. The mean diameter of tumors in each period was 38, 29, and 30 mm, respectively. The percentage of tumors with positive ER expression was 62.5%, 64.3%, and 69.7%, respectively. In terms of surgical procedures, the use of Halsted’s radical mastectomy decreased during each period: from 40.6% of cases to 8.5% and then to 0.4%, while the proportion of breast-conserving therapies increased, from 0% to 12.5%, and finally to 35.9%. The postoperative 10-year survival rates during the three periods were 75.9%, 83.5%, and 84.9%, respectively. The 10-year survival rates of patients with stage II disease during the three periods were 66.2%, 75.7%, and 90.7%, respectively. The prognosis of stage III disease in the three periods also showed a tendency toward improvement, increasing from 37.8% to 64.2%, and finally to 84.5%. CONCLUSION: The survival of patients with stage II and III disease has improved during the past 30 years. Along with the recent advances in drug therapy, the surgical treatment has become less invasive, often because of drug therapy-related modifications.